2. 外语
  3. Life Span About a century ago, the average life span for Americans was about 50 years. /Today, the typical American lives fo

Life Span About a century ago, the average life span for Americans was about 50 years. /Today, the typical American lives fo

admin2016-10-12  70
问题  
选项
答案 Life Span About a century ago, the average life span for Americans was about 50 years. /Today, the typical American lives for around seventy-eight years. /What accounts for such increased longevity? /Between 1900 and 1950, inventions such as refrigeration and sewage treatment meant that/young people were able to survive longer. /Moreover, medical breakthroughs helped contain diseases/such as some fatal ones that killed many children. /These advances helped increase the average life span. /This means that future medical breakthroughs will result in even longer average life span.
解析
转载请注明原文地址:https://kaotiyun.com/show/aOPK777K
0

专业英语四级

相关试题推荐
随机试题
最新回复(0)